NI 43-101 (Standards of Disclosure for Mineral Projects)
National Instrument 43-101 is the Canadian securities rule governing how mining and exploration companies disclose information about their mineral properties — requiring technical reports prepared and signed off by an independent "qualified person."
Any Canadian reporting issuer with mining or mineral exploration interests must support its scientific and technical disclosure — press releases, annual reports, and resource estimates — with a technical report prepared under NI 43-101.
These reports must be prepared, or supervised, by a "qualified person" (QP) — an engineer or geoscientist with relevant experience and professional registration — who takes personal responsibility for the technical content.
NI 43-101 reports use standardized categories for how confident an estimate is: inferred, indicated, and measured mineral resources (in increasing order of geological confidence), and probable and proven mineral reserves once economic viability has been demonstrated. Reports also commonly include a Preliminary Economic Assessment (PEA), pre-feasibility study, or feasibility study.
For investors, NI 43-101 is what separates an independently verified resource estimate from a promotional claim. Tracking new NI 43-101 filings — and the insider and lobbying activity around them — is on Form55's roadmap for mining-sector coverage.